Also, if you live in Brookly (as your profile states), just about any bike is subject to being stolen. That's just life in the big city.

I would suggest that you only invest as much money as you wouldn't mind having stolen one day. Any "nagasawa frames and all that njs stuff" would likely be stolen very quickly as professional thieves will spend their time and efforts on stuff that can be sold easily at a fairly high price such as a nagasawa frame.

So, you sort of have some thinking to do. Either build a bike that you don't mind being locked up in Brooklyn for hours at a time, or build a "sunday bike" that you hold on to all day (I'm not knocking this because that's what I do. I don't even carry locks anymore. If I can't bring my bike in...I don't go in.)